The voltage of R wave in lead aVL improves risk stratification in hypertensive patients without ECG left ventricular hypertrophy.

OBJECTIVES: We tested the hypothesis that the voltages of QRS on ECG improve risk stratification in hypertensive patients without left ventricular hypertrophy on ECG. METHODS AND RESULTS: We studied 2042 initially untreated patients with hypertension (mean age 49 years, 46\% women) without left ventricular hypertrophy on ECG and no history of cardiovascular disease. At entry, all patients underwent diagnostic tests, including 24-h ambulatory blood pressure monitoring and echocardiography. Among the different ECG voltages, the R wave in lead aVL showed the closest association with left ventricle (LV) mass (r = 0.31; P < 0.001), followed by the R wave in D1 (r = 0.25) and the S wave in V3 (r = 0.22). Patients were followed up for a mean of 7.7 years (range 1-22 years), and treatment was tailored individually. During follow-up, there were 188 major cardiovascular events. The relationship between LV voltage and outcome was assessed using a Cox model with adjustment for age, sex, diabetes, smoking, total cholesterol, serum creatinine, LV mass on echocardiography and average 24-h ambulatory blood pressure. A 0.1 mV higher R wave voltage in lead aVL was associated with a 9\% higher risk of cardiovascular disease (95\% confidence interval = 0.04-0.15\%; P < 0.001). Other ECG voltages and minor repolarization changes were not related to clinical outcome. CONCLUSION: Our results show for the first time that the voltage of the R wave in lead aVL improves cardiovascular risk stratification in hypertensive patients without left ventricular hypertrophy on ECG. Its prognostic value is independent of LV mass on echocardiography and 24-h ambulatory blood pressure.